SU727283A1 - Method of producing bent steel-tube branches - Google Patents

Description

one

The invention relates to the processing of metals by pressure and can be used in the manufacture of pipelines.

A known method of manufacturing large diameter bent bends (01220-1420 mm) from twelve-meter pipes in the route and factory conditions and 24 meters sections (paired two-pipes) under the conditions of the route.

In the known method, billets are laid out under bending, fed in the axial direction to the working position and bent at the working position in the marked places with the subsequent removal of the finished drain 1.

The bends manufactured in a known manner have straight sections of 2500, 3000, 2500, and 2200 mm respectively.

Since the bends have a complicated configuration (straight and curved sections of different lengths) it is difficult to dig trenches, digging trenches along a circular curve with an average radius is prohibited, therefore during installation and laying of pipelines into pre-prepared trenches, considerable deviations are allowed (different curvatures of the pipeline and trench profile - vertically and horizontally) and as a result, after welding, when laying in trenches, pipelines experience large internal stresses,

this leads to the fact that sometimes already during the laying of pipes in trenches. there is a fracture of them. Elimination of the resulting marriage causes overhead and hinders the construction of pipelines.

All operations of the known method are performed on one pipe.

The aim of the invention is to increase productivity and reduce production costs.

The goal is achieved by the fact that the supply of billets to the working position is carried out continuously, and after completing the last marked section of each previous billet is bent, subsequent billets are welded to its end to form temporary technological joints, and on temporary technological joints.

The sequence of operations of the proposed method is shown in FIG. 1, 2 and 3.

The fabrication of the bends by cold bending on pipe bending machines is as follows.

The pipe 1 (the blank for the production of taps) is laid on the cradle 2 of the bending machine 3 (see Fig. 1). Then the pipe 1 is pressed against the bending shoe 5 by the resistant bending lodgement 4.

Raising the hydraulic jacks 6 and 7 and together with them the cradle 2 to a predetermined limit, the pipe is destroyed. Then the cradle 2 and 4 are started in the lower position, the pipe 1 is moved by the required amount and the bending operation is repeated.

At the same time, as the length of the pipe being bent is used, here (on the pipe bending machine) temporary technological joints (joint N, etc.) are welded next pipes 8, which are bent in the same order. On the opposite side of the machine, the bends are made by gas cutting, and the cutting is performed according to temporary technological joints.

In order to ensure correct geometry at the ends of the fabricated taps (minimum ellipse: edges) of the bend zone. When bending, the taps are located at a distance of at least 200 mm (see TU-102-64-75) from the temporary technological joints.

Example. The proposed methods are made of bent bends 01020 - 01420 mm with a bending angle of 5-6 °, 6 pm long. When this metal TRG is metal, the tolerances at bending and the radius of curvature of the taps meet the requirements of the normals - .-, HB 10-65, HB 13-65 and TU 102-64-75.

The introduction into production of the proposed method of manufacturing curved bends will allow them to be widely used instead of welded ones, which will give the national economy a great economic effect.

In addition, the use of bending taps made by the proposed method will significantly improve labor productivity and quality of work during the installation of trunk pipelines and dramatically reduce transportation costs for transportation.

Claims (1)

Invention Formula A method of manufacturing bent steel bends from large-diameter pipes, in which the tube blanks are marked under bending, axle axially at the working position and bending at the working position at the marked places, followed by removal of the ready-made tap, characterized in that production costs, the supply of billets to the working position is carried out continuously, and after completion, bend the last marked section of each previous billet to its end weld The subsequent billet is formed with the formation of temporary technological joints, and the removal of the finished drainage is carried out by gas cutting mainly along temporary technological joints. Sources of information taken into account during the examination 1. Halperin A. I. Construction of pipe bending machines for the construction of main pipelines. M., “Mashgiz, 1959, p. 6-60. y /// 7 ////////////////// y y // //////// ////////////// ////////// Fig.Z